CAN COMMUNICATION SYSTEM Open in Bus 5 Main Bus Line

DESCRIPTION

There may be an open circuit in one of the CAN main bus lines when the resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.

Symptom Trouble Area
Resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.

  • CAN main bus lines or connector

  • Central gateway ECU (network gateway ECU)

  • Power management control ECU

  • CAN No. 4 junction connector

  • CAN No. 7 junction connector

    (w/ Parking Assist Monitor System (w/o Parallel Parking Assist Function))

This malfunction is not related to the lines of a CAN branch or to ECUs or sensors connected to a CAN branch.

WIRING DIAGRAM

B001L2RE03
for RHD or without Parking Assist Monitor System (w/o Parallel Parking Assist Function)
*a Power Management Control ECU
*b Central Gateway ECU (Network Gateway ECU)
*c CAN No. 4 Junction Connector
B001KX4E24
w/ Parking Assist Monitor System (w/o Parallel Parking Assist Function)
*a Central Gateway ECU (Network Gateway ECU)
*b CAN No. 4 Junction Connector
*c CAN No. 7 Junction Connector
*d Power Management Control ECU

CAUTION / NOTICE / HINT

Note


  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here

  • Before measuring the resistance of the CAN bus, turn the power switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

    Click here

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here

Tech Tips


  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.

  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE


  1. CHECK VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      for RHD or without Parking Assist Monitor System (w/o Parallel Parking Assist Function) A
      w/ Parking Assist Monitor System (w/o Parallel Parking Assist Function) B

    B

    CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN NO. 4 JUNCTION CONNECTOR) Click here

    A

  2. CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN NO. 4 JUNCTION CONNECTOR)


    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

    2. Disconnect the H191 CAN No. 4 junction connector.

    3. Measure the resistance according to the value(s) in the table below.

      B001N49C20
      *a

      Front view of wire harness connector

      (to CAN No. 4 Junction Connector)

      		 *b to Power Management Control ECU
      *c to Central Gateway ECU (Network Gateway ECU) - -
      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H191-5 (CANH) - H191-11 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Power management control ECU
      H191-6 (CANH) - H191-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)
      Result
      Result Proceed to
      OK A
      NG (Line to central gateway ECU (network gateway ECU)) B
      NG (Line to Power management control ECU) C

    A

    REPLACE CAN NO. 4 JUNCTION CONNECTOR

    C

    CHECK FOR OPEN IN CAN BUS LINES (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 JUNCTION CONNECTOR) Click here

    B

  3. CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - CAN NO. 4 JUNCTION CONNECTOR)


    1. Reconnect the H191 CAN No. 4 junction connector.

    2. Disconnect the H188 central gateway ECU (network gateway ECU) connector.

    3. B001LE1C69
      *a

      Front view of wire harness connector

      (to Central Gateway ECU (Network Gateway ECU))

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H188-15 (CA5H) - H188-16 (CA5L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - CAN NO. 4 JUNCTION CONNECTOR)

  4. CHECK FOR OPEN IN CAN BUS LINES (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 JUNCTION CONNECTOR)


    1. Reconnect the H191 CAN No. 4 junction connector.

    2. Disconnect the H3 power management control ECU connector.

    3. B001MMHC48
      *a

      Front view of wire harness connector

      (to Power Management Control ECU)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H3-34 (CA2H) - H3-35 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - CAN NO. 4 JUNCTION CONNECTOR)

  5. CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN NO. 4 JUNCTION CONNECTOR)


    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

    2. Disconnect the H191 CAN No. 4 junction connector.

    3. Measure the resistance according to the value(s) in the table below.

      B001N49C21
      *a

      Front view of wire harness connector

      (to CAN No. 4 Junction Connector)

      		 *b to CAN No. 7 Junction Connector
      *c to Central Gateway ECU (Network Gateway ECU) - -
      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H191-5 (CANH) - H191-11 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 7 junction connector
      H191-6 (CANH) - H191-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)
      Result
      Result Proceed to
      OK A
      NG (Line to central gateway ECU (network gateway ECU)) B
      NG (Line to CAN No. 7 junction connector) C

    A

    REPLACE CAN NO. 4 JUNCTION CONNECTOR

    C

    CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN NO. 7 JUNCTION CONNECTOR) Click here

    B

  6. CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - CAN NO. 4 JUNCTION CONNECTOR)


    1. Reconnect the H191 CAN No. 4 junction connector.

    2. Disconnect the H188 central gateway ECU (network gateway ECU) connector.

    3. B001LE1C69
      *a

      Front view of wire harness connector

      (to Central Gateway ECU (Network Gateway ECU))

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H188-15 (CA5H) - H188-16 (CA5L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - CAN NO. 4 JUNCTION CONNECTOR)

  7. CHECK FOR OPEN IN CAN MAIN BUS LINES (CAN NO. 7 JUNCTION CONNECTOR)


    1. Reconnect the H191 CAN No. 4 junction connector.

    2. Disconnect the P36 CAN No. 7 junction connector.

    3. Measure the resistance according to the value(s) in the table below.

      B001N49C22
      *a

      Front view of wire harness connector

      (to CAN No. 7 Junction Connector)

      		 *b to CAN No. 4 Junction Connector
      *c to Power Management Control ECU - -
      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      P36-1 (CANH) - P36-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 4 junction connector
      P36-3 (CANH) - P36-9 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Power management control ECU
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 4 junction connector) B
      NG (Line to Power management control ECU) C

    A

    REPLACE CAN NO. 7 JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 4 JUNCTION CONNECTOR - CAN NO. 7 JUNCTION CONNECTOR)

    C

  8. CHECK FOR OPEN IN CAN BUS LINES (POWER MANAGEMENT CONTROL ECU - CAN NO. 7 JUNCTION CONNECTOR)


    1. Reconnect the P36 CAN No. 7 junction connector.

    2. Disconnect the H3 power management control ECU connector.

    3. B001MMHC48
      *a

      Front view of wire harness connector

      (to Power Management Control ECU)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H3-34 (CA2H) - H3-35 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - CAN NO. 7 JUNCTION CONNECTOR)